1. Field of the Invention
The present invention relates to an internal combustion engine, and more particularly, to an internal combustion engine comprising a cylinder block made of a light-alloy and having a wall, around the cylinder bore, comprised of a cylindrical fiber-reinforced portion which is formed of a mixture of an alumina-based fiber and a carbon fiber with a light alloy matrix; and a piston having a piston ring mounted thereon and slidably received in the cylinder bore.
2. Description of the Prior Art
There is conventionally known an internal combustion engine wherein a cylinder block includes a cylinder sleeve comprised of an inner shell made of a partially stabilized zirconia and an outer shell made of a gray cast iron, as disclosed in U.S. Pat. No. 4,544,607.
However, this internal combustion engine is not advantageous in providing a decrease in weight, because the outer shell in the cylinder sleeve is made of the cast iron.
Also a construction has been suggested wherein the cylinder block is produced in a casting process by using a light alloy, and the wall of the cylinder bore is comprised of a cylindrical fiber-reinforced portion which is formed of a reinforcing fiber and a light alloy matrix. In this case, however, there have been problems with the strength of the cylindrical fiber-reinforced portion, the sliding characteristics of the mating piston and piston ring with the cylinder, the machinability, and the like.